Internet at Competitions

[Koko Ed]

FIRST is deadly serious about the Wifi issue. They had Wifi sniffers at the champs tracking down people who were setting up Wifi hotspots. And every event I went to they tell teams repeatedly to turn off any wifi they set up. After the fiasco of 2012 they are not in the mood to have that happen again and trust me you do not want to have happen to you what happened to the dude who was causing mischief that day.

[coalhot]

Originally Posted by yash101

Also, you say, don't use WiFi in the competitions, but you don't really explain why. Also, yes, they will get angry at you, but it isn't a bad thing, like how you are making it sound. That is to just keep the fields working properly. WiFi is a thing that is quite useful in competitions because it will network devices together, allowing them to communicate. That is the reason why you use Bluetooth in competitions!

This topic has been beaten to death in numerous other threads. Do a search, you'll find them.

As for the WIFI, I agree that offering it would provide many benefits, not limited to teams being able to use the internet, but also to less interference with the field because teams aren't setting up their own connections.

That being said, it's not on the teams to bring their own 4g hotspot and router and set up their own network. It's on FIRST and the event staff to allow it and set it up. Please don't break the rules, the FTA and field staff have a very difficult job to do, and they don't need teams and individuals causing them numerous delays to the event schedule because they decide to do something unwise.

[sanddrag]

At the Long Beach regional we've used Clear WiMax USB modems, with Cradlepoint routers and a wired network. Of course, this only works within a couple miles of a Clear (sprint) WiMax tower, and the bandwidth is not great.

[yash101]

Originally Posted by sanddrag

At the Long Beach regional we've used Clear WiMax USB modems, with Cradlepoint routers and a wired network. Of course, this only works within a couple miles of a Clear (sprint) WiMax tower, and the bandwidth is not great.

the max data rate is 14Mbps, 3 times as fast as my home's internet. The funny thing is that I live within the urban areas of PHX. My community is a tad newer so we have all the good technology.

[philso]

Originally Posted by yash101

I mean a small difference, just in the antenna, like 2.6GHz instead of 2.4!

How would changing the antenna will change the bandwith that the radio operates in. In the radio systems that I worked on (precursor to WiFi), one would have to make a change in the radio itself to make that happen.

The FCC, a US government agency, manages the radio frequency spectrum in the US. The ISM bands that WiFi operates on are well defined by FCC regulations. By straying outside of the defined bandwidth, you may be interfering with some other radio system, possibly with very serious consequences for the operator of that system. Do it for long enough and someone from the FCC may visit you and slap you with a fine.

Originally Posted by antimatter_john

Well it's a good way to scout with the possibilities of it.

Also it allows teams to make something cool with their app or web app using the internet.

Why is it a superior way to scout?

Is the purpose of the team to compete at a tournament or to make cool phone apps or web apps?

Originally Posted by EricH

Interference. That's why no WiFi. Field working properly is HUGE! You weren't around in 2012, I don't think--get your hands on a copy of the Einstein Report from that year, and see just what can go wrong if either the field or the robots aren't working properly.

The radio band can carry only so much data at any particular time. Would you rather it be data for controlling your robot on the field or data for scouting?

[saikiranra]

Originally Posted by philso

Is the purpose of the team to compete at a tournament or to make cool phone apps or web apps?

It opens a whole world of possibilities. If you have internet in the pits and in the stands, you can seamlessly and effortlessly transfer data to create comprehensive match strategies. In addition, you can talk to the scouts via chat and ask them for opinions and suggestions all from within your pit. It also helps with collaborative scouting, for something like CowScout, where you want multiple sources of data from different events.

[techhelpbb]

I agree with the others:

FIRST made a decision to use WiFi.
Way back when....before the cRIO...I recall many conversations about how great WiFi would be.

Okay so we have WiFi.
On the field side you have Cisco, on the robot side to date: D-Link and monitoring for the lot on 5GHz spectrum.
There is monitoring on the 2.4GHz spectrum but it's hard to enforce it because that spectrum is typically a mess.

On the high side of the 5GHz spectrum you have bands assigned to radar.
Luckily I've yet to see a FIRST team deploy 5GHz radar on a robot .

That said: if there are multiple fields and you are in the 5GHz WiFi bands you should stay out of range of the fields (read - just don't do it). There are only so many channels in that 5GHz WiFi band and it's *extremely* likely with anything that can bond 2 or more channels (for 300Mbps or greater) you will short change the field merely by existing. Plus that can cause chaos with the robot radios as they are capable of discovering that interloper network.

Now the issue starts turning into this: Apple devices are increasingly happy to use the 5GHz WiFi spectrum. So ad-hoc networks between Apple users on 5GHz are point and click (and mind you that's not even for Internet). Per the Einstein report more and more mobile devices are using chipsets with 5GHz WiFi support. All of those can click their way into becoming an issue and per that report have become an issue (the details of that have been covered at length).

All that said: when I helped propose a 2015 control system I intentionally proposed a secondary low frequency radio for field related traffic leaving all the WiFi spectrums available. The entire point was to prevent the field safety mechanism from disabling robots because of radio link level issues. I proposed to do this using 3rd party modules with FCC approval attached to them. This meant that you could swap the hardware modules and the sockets were attached to the MCU in such a way that a very wide selection of frequencies were available below 1GHz. That meant you could accommodate radio regulators everywhere on Earth merely by swapping those modules. Mind the point that whatever was on the WiFi spectrum was no longer my concern. If a team wanted to use 2.4GHz on their robot for their vision systems it would not matter. If a team wanted to use 5GHz on their robot for their crazy Theremin controller not my issue.

As it stands FIRST (speaking as a 3rd party) has a vested interest in not altering the 2014 field system because they have end-of-life Cisco gear that is expensive and likely a pile of D-Link radios they can waste. Not to mention I noticed that last year antennas were changed which added some cost. I also noticed some additional changes in the way WiFi spectrum use was monitored.

I have, in the past, had to ask teams to turn off their 5GHz WiFi near the field. I will not say whom. There was a WiFi router with an open network sitting literally next to the field. Please just do not do this. You have bluetooth and other choices. Heck if you are clever you have infrared. Do not risk making issues on the field merely because you have zeal to do something interesting. Situations like the Einstein report need to never happen again and now that it has been investigated I doubt anyone will be able to plead ignorance of the risk.

In the past at the Mount Olive district event WiFi in the 2.4GHz spectrum was available but it was swamped by people with their phones and just shear demand. In reality the same bandwidth throttling technology now in use on the fields would help with that...but I bet very few events have any Internet available that actually has controlled bandwidth usage because that equipment adds cost (yes it can be done with a PC but most people just buy the finished product and have no interest in hacking it themselves). So with that all said: I personally am in favor of offering teams Internet access - by twisted pair ethernet in the pits. This has the distinct advantage of consuming zero radio spectrum unless the event coordinators decide to backhaul the traffic with WiFi. Still bandwidth controls should exist. However it should be much easier to reliably cap any team's Internet traffic if they are wired to the network as there should be much less risk of packet loss. For the teams this would mean they could use bluetooth or cellular near the field and dump their data at zero risk to the venue at the pits (these days there is way more than enough cheap storage to buffer up data in a smartphone).

[philso]

Originally Posted by saikiranra

It opens a whole world of possibilities. If you have internet in the pits and in the stands, you can seamlessly and effortlessly transfer data to create comprehensive match strategies. In addition, you can talk to the scouts via chat and ask them for opinions and suggestions all from within your pit. It also helps with collaborative scouting, for something like CowScout, where you want multiple sources of data from different events.

What you are saying is true. It does not answer my question regarding what your priorities are. As I stated earlier in my post, the WiFi bandwidth can carry only so much data. Do you want to use it to control your robots or do you want to use it chat and pass around data about robots that would kill on the field if they could be made to operate? This is an engineering competition. In engineering, one has to make tough choices based on one's priorities.

Originally Posted by techhelpbb

I personally am in favor of offering teams Internet access - by twisted pair ethernet in the pits. This has the distinct advantage of consuming zero radio spectrum unless the event coordinators decide to backhaul the traffic with WiFi.

This is also true. The data rates could then much higher than what you could achieve with WiFi. It would also take a lot of work to set up properly. The type of equipment used to create a such network is not typically meant to be moved around and I suspect that after some time, some of the connections would become flaky and teams would complain loudly here.

[mechanical_robot]

Originally Posted by DonRotolo

Why in the world would you need Internet access for scouting? What is it you need from outside the venue?

Well it's a good way to scout with the possibilities of it.

Also it allows teams to make something cool with their app or web app using the internet.

[1306scouting]

1306 sets up a network for scouting; this allows us to backup our data offsite as well as being essential for CrowdScout so that other teams can get data updates.

We tether a phone with an (unlimited) data connection over Bluetooth to Computer A.

Computer A is set to share this internet connection from the Bluetooth PAN to Ethernet, which is fed to a router (with WiFi disabled). The router shares it among our network, which is entirely Ethernet. (Ethernet allows us to expand the network by using switches if needed.)

Sharing files on our local network can get complicated because we run across Windows, Linux, and OS X. Generally we set up a SMB/SMB2 share hosted off of Computer A if we need to exchange many files.


The system is very scalable and incredibly reliable - only one wireless link is used, so there's rarely issues with interference (as compared with a Bluetooth many-device network). We're looking at getting rid of that link, too, using a USB OTG cable and USB-to-Ethernet adapter.

[Woolly]

Last year, to access our SVN server during competition, I shared my internet connection from my phone to my computer while in the pits.